Generally, a core structure is stored in a storage container and then the storage container is carried into a nuclear-reactor storing housing. A typical storage container includes a storage-container upper cover, a storage-container body, and a storage-container bottom cover. Conventional core-structure storing methods are disclosed in Patent Documents 1 and 2.
The conventional core-structure storing method disclosed in Patent Document 1 includes a step of craning down a storage-container upper cover above a core structure, which is inserted into a nuclear-reactor vessel in a cavity, while water in the cavity is discharged; a step of attaching the storage-container upper cover to the core structure; a step of craning down the storage-container body so that the bottom of the storage-container body is closely in contact with the top surface of the nuclear-reactor vessel; a step of craning up the core structure with the storage-container upper cover so that the core structure with the storage-container upper cover is positioned inside the storage-container body; a step of attaching the storage-container upper cover to the storage-container body; a step of craning up the storage-container body to be positioned at a certain level; a step of positioning a storage-container bottom cover under the storage-container body; and a step of attaching the storage-container bottom cover to the storage-container body by craning up the storage-container bottom cover.
In the above conventional core-structure storing method, a moving device is set in the cavity and the storage-container bottom cover is placed on the moving device. The moving device is moved such that the storage container is positioned under the storage-container body.
Because the core structure, which is stored in the storage container is highly radioactive, there is a demand for means and measures capable of further reducing irradiation on an operator.
Patent Document 1: Japanese Patent Application Laid-open No. 2004-69354
Patent Document 2: Japanese Patent Application Laid-open No. 2003-215294